1. Field of the Invention
The present invention is related to the field of liquid bird feeders and, more particularly, to a top-fill hummingbird feeder.
2. Description of the Related Art
People who live in an area inhabited by hummingbirds frequently try to promote their presence by the use of hummingbird feeders. Hummingbird feeders differ from ordinary bird feeders because hummingbirds feed on nectar or simulated nectar, which are liquid, instead of the dry food consumed by most birds. Simulated nectar is typically formed from water sweetened with sugar or honey. In many hummingbird feeders, the nectar (or simulated nectar) is stored in a reservoir and conveyed to simulated flowers where a perch may be provided so that the hummingbird can land and, having a long, slender beak, insert it into the access apertures in the simulated flower and feed.
Most hummingbird feeders have one of two basic designs. One includes an inverted top container which empties into a lower reservoir or feeding basin from which the birds feed. The vacuum at the top of the container (or put another way, the outside air pressure) keeps the liquid in the top container from draining out too rapidly. The other common feeder design consists of a container with holes in its cover through which the hummingbirds reach to feed. This latter style of feeder suffers from the problem that it must be refilled very often, because the level of food is constantly being reduced by the feeding.
The so-called “vacuum-type” feeders also have problems. For example, they can only be filled by dismantling the feeder and removing the top container from its feeding position. Ordinarily, the consumer must invert the feeder in order to refill it, with the attendant risks of spillage, and requires a certain amount of manual dexterity to create the necessary vacuum. Moreover, because a vacuum is required, these designs are limited to a single opening for filling and cleaning. This opening is typically small, which restricts access to the interior of the container and makes it more difficult to effectively clean the container. Additionally, vacuum feeders can corrode or be inefficient, permitting the nectar to leak and creating an increased risk of insect contamination.
One product which has been available in the market is the Garden Song Top Fill Hummingbird Feeder from Opus Incorporated. The Opus feeder includes an upstanding liquid container with a large top opening and a small cylindrical lower opening which is screw-threaded into an upstanding cylindrical collar positioned in the center of a feeding basin or liquid tray. The top opening is closed with a cover that seals the container to create a vacuum as the liquid level recedes downwardly in the container. An internal, rotatable ring or valve mechanism has an upstanding cylindrical wall which surrounds the cylindrical collar inside the feeding basin.
The wall of the cylindrical collar has a plurality of ports, and the cylindrical wall of the rotatable ring has a plurality of corresponding openings. When the openings in the rotatable ring are aligned with the ports of the collar using an externally accessible lever, nectar can flow out of the container lower opening, through the aligned ports and openings, and into the feeding basin or liquid tray. When the rotatable ring is rotated using the externally accessible lever, so that its openings are not aligned with the ports of the collar, the nectar flow from the container to the feeding base is cut off. In this condition, the cover can be removed from the container top opening for (re)filling the container without nectar in the container flowing out through the collar to flood and overflow the feeding base or liquid tray. This design also permits the top opening to be large enough to facilitate easy cleaning of the bottle. This feeder is described in co-pending U.S. application Ser. No. 11/434,020, which is hereby expressly incorporated herein by reference.
There have also been modular designs for hummingbird feeders in which a common functional feeding module is utilized in conjunction with changeable decorative outer claddings. However, such prior art hummingbird modular feeders suffer the same drawbacks as discussed above.